• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

To investigate how the concentration of sodium thiosulphate as it is diluted with water and then added to hydrochloric acid, affects the rate of reaction.

Extracts from this document...


Sodium thiosulphate investigation Aim: To investigate how the concentration of sodium thiosulphate as it is diluted with water and then added to hydrochloric acid, affects the rate of reaction. Prediction: I think that as I dilute the sodium thiosulphate with water and then add it to the hydrochloric acid, the time for the rate of reaction will increase. I have followed a special theory for this. The theory is the collision theory, which states, as you increase a substance there are more particles in it resulting in more collisions. This theory can also work vice versa because in this experiment we will be decreasing the concentration of sodium thiosulphate resulting in less collisions, therefore extending the time for the reaction to take place. In a low concentration, the particles will be few and widely spread. This means that the number of reactions will be limited because fewer particles will meet. At higher concentrations there are more particles and so they probability of them coming into contact with other particles is increased. But in this experiment we are swiftly decreasing the concentration of sodium thiosulphate. This theory is applied when the reaction is applied. ...read more.


I also made sure someone always stayed on top of the beaker to observe when the cross-disappeared. I always made sure that I never moved the beaker a lot because I didn't want any more collisions resulting in a faster rate of reaction. I always repeated my exercise 3 times, so I could get a more accurate mean average. I used the Internet a lot to research on rate of reaction, so I could extend my knowledge on this subject, giving better observations. Quantities used: Experiment no. Volume of sodium thiosulphate CM3 Volume of water used CM3 Volume of HCL used CM3 Total volume CM3 1. 35 00 05 40 2. 30 05 05 40 3. 25 10 05 40 4. 20 15 05 40 5. 15 20 05 40 6. 10 25 05 40 7. 05 30 05 40 Results: (on graph paper) Conclusions: From my graph I can see that most of my results were correct, although I did have an anomalous result. My results agree with my prediction because I predicted that the lower the concentration of sodium thiosulphate, and the higher the amount of water, the longer the reaction would take to occur. ...read more.


These were probably due to me rushing the measuring of each solution. We were set a certain time limit of one 50-minute lesson, to get each solution done at least twice so I might have rushed. Other reasons for these anomalous results could be that the eye could also have made mistakes in judging whether or not the cross-had actually completely disappeared. If the same person watching the reaction was working the timer, errors could occur in their co-ordination. Using a burette to measure. This would remove the measuring errors associated with measuring cylinders, as they are correct to 0.1 cm where measuring cylinders are only 0.4. Burettes are a far more accurate way of measuring the correct amounts. Use light sensors to detect when the cross is no longer visible. The experiment could be connected to a light sensor, and to a timer. These light sensors will detect when there is no light shining through the substance. This would automatically stop the timer and therefore make the experiment fairer and more accurate. Doing each solution on separate occasions and repeating them more than three times giving me a better average could have extended my investigation. But these choices were out of my control. Altogether I am quite pleased with my investigation and my results. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Patterns of Behaviour section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Patterns of Behaviour essays

  1. Experiment to Investigate the Rate of Reaction between Hydrochloric Acid and Sodium Thiosulphate, with ...

    is due to the collision theory, which happens while the reactions take place, which is by 'Increasing the concentration of a substance in solution means that there will be more particles per dm3 of that substance' (www. gcsescience.com). So the more particles there are in the substance 'the more will

  2. The aim of this coursework is to investigate the rate of reaction between sodium ...

    Prediction In the reaction between sodium thiosulphate solution and hydrochloric acid, a yellow precipitate of sulphur is formed. I predict that as you increase the concentration of sodium thiosulphate; the solid sulphur will be produced more quickly and there will be less time before the cross can be seen.

  1. The aim is to see how the concentration of sodiumthiosulphate (Na2 S2 03) affects ...

    Variables Surface area of solid - The surface area has an effect on the rate of reaction. If the solid has a large surface area then there are more opportunities for collisions to occur between the molecules. If the surface area is small, collision can only occur with the outer atoms and is therefore limited.

  2. The aim of this investigation is to see how the concentration of sodium thiosulphate ...

    A catalyst is usually a transition metal, a transition metal oxide (see uses of transition metals) or an enzyme in living cells. An exception is aluminium oxide, used in the Cracking of Hydrocarbons. How does a Catalyst work? A catalyst works by providing a convenient surface for the reaction to occur.

  1. This experiment's title is: "investigate how the concentration of Sodium Thiosulphate affects the rate ...

    * The overall volume. * The temperature. * The size and shape of beaker used. * The position from where you observe the reaction - the 'X' may be more obscured at different angles of perception. * The same 'X' must be used - any change in size etc.

  2. To investigate a factor that affects the rate of reaction and why?

    proceeds more quickly: Low concentration High concentration Increased concentration means increased numbers of particles, resulting in a greater number of collisions and therefore an increased rate of reaction. A graph plotted should produce a positive gradient. Exothermic and Endothermic reactions: There are two types of reactions: 1)

  1. The aim of my experiment is to see how temperature affects the reaction rate ...

    So as the temperature rises the reaction rate does as well, consequently, as the temperature decreases so does the reaction rate. The 'rule of the thumb' theory for most reactions (including this one) says that as the temperature raises every 10oC the reaction rate doubles.

  2. To investigate what affects the rate of reaction between Sodium Thiosulphate and Hydrochloric Acid.

    I predict that when the temperature increases then the rate of reaction will also increase. I think this because, when the temperature increases, the particles of the liquid would move faster and cause more collisions. So, when the temperature increases, there is more kinetic energy, so there are more collisions

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work